Processes to prepare small molecular thiophene compounds

Abstract

A process composed of subjecting a reaction mixture comprising a reaction medium, a coupling agent, and a precursor to a coupling temperature to preferentially form a desired small molecular thiophene compound in a single-step synthesis, wherein the precursor consists of: (i) an optional divalent linkage, and (ii) a plurality of thiophene units, each thiophene unit being represented by structure (A) wherein each thiophene unit is bonded at either or both of the second ring position and the fifth ring position.

1. A process comprising:
 subjecting a reaction mixture comprising a reaction medium, a coupling agent, and a precursor to a coupling temperature to preferentially form a desired small molecular thiophene compound in a single-step synthesis, 
 wherein the precursor consists of:
 (i) an optional divalent linkage, and 
 (ii) a plurality of thiophene units, each thiophene unit being represented by structure (A) 
 
 
       
         
           
           
               
               
           
         
         wherein each thiophene unit is bonded at either or both of the second ring position and the fifth ring position, 
         wherein m is 0, 1, or 2, 
         wherein each thiophene unit is the same or different from each other in terms of substituent number, substituent identity, and substituent position, 
         wherein each R 1  is independently selected from the group consisting of:
 (a) a hydrocarbon group, 
 (b) a heteroatom containing group, and 
 (c) a halogen. 
 
       
     
     
       2. The process of  claim 1 , further including isolating the desired small molecular thiophene compound to result in a small molecular thiophene compound. 
     
     
       3. The process of  claim 1 , wherein for the small molecular thiophene compound there is at least one thiophene unit where R 1  is present at the third ring position or the fourth ring position, or at both the third ring position and the fourth ring position, and
 wherein for any two adjacent thiophene units as represented by structure (A1): 
 
       
         
           
           
               
               
           
         
       
       there is excluded the simultaneous presence of the same or different R 1  at the 3-position of one thiophene unit and at the 3′-position of the other thiophene unit. 
     
     
       4. The process of  claim 1 , wherein the precipitation in the reaction mixture commences when the concentration of the desired small molecular thiophene compound reaches a saturation point in the reaction medium. 
     
     
       5. The process of  claim 1 , wherein the desired small molecular thiophene compound is preferentially formed in an amount ranging from about 30% to about 90% by weight. 
     
     
       6. The process of  claim 1 , wherein the coupling temperature ranges from about room temperature to about 150 degrees C. 
     
     
       7. The process of  claim 1 , wherein the coupling temperature ranges from about 30 to about 140 degrees C. 
     
     
       8. The process of  claim 1 , wherein the reaction medium is tetrahydrofuran, toluene, chloroform dichloromethane, chlorobenzene, 1,2-dichloroethane, xylene, heptane, mesitylene, nitrobenzene, acetonitrile, or cyanobenzene, or a mixture thereof. 
     
     
       9. The process of  claim 1 , wherein the coupling agent is FeCl 3 , RuCl 3 , MoCl 5 , or a mixture thereof. 
     
     
       10. The process of  claim 1 , wherein the number of the thiophene units in the precursor ranges from 2 to 8. 
     
     
       11. The process of  claim 1 , wherein the number of the thiophene units in the small molecular thiophene compound is selected from the group consisting of 6, 8, 12, and 16. 
     
     
       12. The process of  claim 1 , wherein the precursor is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         or a mixture thereof, 
         wherein each R is independently selected from the hydrocarbon group, the heteroatom containing group, and the halogen. 
       
     
     
       13. A process comprising:
 subjecting a reaction mixture comprising a reaction medium, a coupling agent, and a precursor to a coupling temperature to preferentially form a desired small molecular thiophene compound in a single-step synthesis, wherein precipitation in the reaction mixture spontaneously occurs and the precipitate includes the desired small molecular thiophene compound, 
 wherein the precursor consists of:
 (i) an optional divalent linkage, and 
 (ii) a plurality of thiophene units, each thiophene unit being represented by structure (A) 
 
 
       
         
           
           
               
               
           
         
         wherein each thiophene unit is bonded at either or both of the second ring position and the fifth ring position, 
         wherein m is 0, 1, or 2, 
         wherein each thiophene unit is the same or different from each other in terms of substituent number, substituent identity, and substituent position, 
         wherein each R 1  is independently selected from the group consisting of:
 (a) a hydrocarbon group, 
 (b) a heteroatom containing group, and 
 (c) a halogen. 
 
       
     
     
       14. The process of  claim 13 , further including isolating the desired small molecular thiophene compound to result in a small molecular thiophene compound. 
     
     
       15. The process of  claim 13 , wherein for the small molecular thiophene compound there is at least one thiophene unit where R 1  is present at the third ring position or the fourth ring position, or at both the third ring position and the fourth ring position, and
 wherein for any two adjacent thiophene units as represented by structure (A1): 
 
       
         
           
           
               
               
           
         
       
       there is excluded the simultaneous presence of the same or different R 1  at the 3-position of one thiophene unit and at the 3′-position of the other thiophene unit. 
     
     
       16. The process of  claim 13 , wherein the precipitation in the reaction mixture commences when the concentration of the desired small molecular thiophene compound reaches a saturation point in the reaction medium. 
     
     
       17. The process of  claim 13 , wherein the desired small molecular thiophene compound is preferentially formed in an amount ranging from about 30% to about 90% by weight. 
     
     
       18. The process of  claim 13 , wherein the coupling temperature ranges from about room temperature to about 150 degrees C. 
     
     
       19. The process of  claim 13 , wherein the coupling temperature ranges from about 30 to about 140 degrees C. 
     
     
       20. The process of  claim 13 , wherein the reaction medium is tetrahydrofuran, toluene, chloroform dichloromethane, chlorobenzene, 1,2-dichloroethane, xylene, heptane, mesitylene, nitrobenzene, acetonitrile, or cyanobenzene, or a mixture thereof. 
     
     
       21. The process of  claim 13 , wherein the coupling agent is FeCl 3 , RuCl 3 , MoCl 5 , or a mixture thereof. 
     
     
       22. The process of  claim 13  wherein the number of the thiophene units in the precursor ranges from 2 to 8. 
     
     
       23. The process of  claim 13 , wherein the number of the thiophene units in the small molecular thiophene compound is selected from the group consisting of 6, 8, 12, and 16. 
     
     
       24. The process of  claim 13 , wherein the precursor is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         or a mixture thereof, 
         wherein each R is independently selected from the hydrocarbon group, the heteroatom containing group, and the halogen.